Ranking the Most Important on Offense: No. 19

The rundown: Irwin, a 6-foot-4, 308-pound sophomore from Mustang, Okla., currently shares the reserve left guard spot on the depth chart with Stephen Good. He participated in seven contests last year, playing a season-high 19 snaps against Iowa State. Irwin had a pair of knockdowns in that game. In addition to his backup role on the offensive line, Irwin also blocked for the field goal unit.

Expectations for 2011: He'll continue to be an important component in solidifying just how deep this O-line is. However, Irwin is behind arguably one of the conference's top three to four guards in starter Gabe Ikard, so his time could be limited there. So, his most valuable role will continue to be that of the field goal team.